To unlock an iPhone, Samsung Galaxy phone, or any other phone for that matter, an IMEI unlock is the most recommended option. This is because hardware and software unlocks only work on a temporary basis and whenever such a device is updated to a new OS firmware or baseband, the device gets relocked again.

Unlock codes may unlock some phone brands, but they are not recommended as well. The problem is that this form of unlocking is basically a software unlock too and may relock the phone when its baseband or firmware gets updated. Also, entering a nonfunctional or wrong unlock codes many times may render the device useless.

So that is why mostly factory unlock IMEI method is used by phone owners. However, there are some reasons why even this method may not work to make your device SIM-free. The three most common ones are as follows:

1. The device is blacklisted or blocked

If you are try to apply or take advantage of an IMEI unlock solution instead of a software unlock on a phone that is blacklisted or blocked, there are no chances of things working out. That’s because a blacklisted device has been reported as stolen or lost, and it won’t work on any network carrier or even restore properly, which is required for an IMEI unlock.

Likewise, a blocked phone is the phone that is associated with the owner having unpaid bills. Carriers block the service, after which the phone is considered as deactivated. A factory IMEI unlock solution requires the phone to be activated before an order can be placed, so chances of it working or almost impossible.

2. Your IMEI code is wrong

An IMEI unlock service requires a 15 digit code to be sent for the purpose of factory unlock. However, sending the wrong code or entering any one of the digits as wrong would mean the unlock service won’t work on your device.

If you are not sure of your IMEI code, find it out by using an IMEI checker for your respective device or search on the web on how to find the IMEI cod for your device within the phone itself.

3. There is an activation lock

If you are trying to unlock an iPhone with IMEI unlock method, make sure there is no activation lock, because it needs to be disabled or bypass before the device works on any other carrier or gets SIM-free.

An activation lock means that the previous iPhone owner forgot to remove his Apple ID or disable the activation lock. You can search for how to disable the activation lock before applying the IMEI solution.